While the invention will be described with reference to the baking of chickens, which are the most common baked meat or poultry commercially available, and is particularly suited to roasting chickens, the invention is not solely limited to use with chickens and may be used on other items baked or roasted in an oven.
Ovens for baking chickens and the like product come in many forms. One of the most popular designs uses convection heat from a fan, and the product within the oven may be rotating on a rack, or stationary. Rotating is however generally thought to be the most even baking, as all products on each tray on the rack can experience the same heat history. The heat source is generally electric elements, or gas or fuel fired by way of a heat exchanger.
When baking chickens in particular, the bake and moisture retention in the product is greatly improved by the use of low pressure but high humidity steam. The finish on the outside skin of the chicken is generally glossier and crispier, with a golden colour. The method of introducing steam into the oven is generally achieved by use of a quick response boiler or steam generator. In this process the water is either kept just below boiling point and raised beyond boiling point when steam is required, or water is introduced over heated ballast, in measured amounts.
These systems have generally fallen out of favour because the boiler or steam generator is remote to the oven chamber itself and requires ongoing service and maintenance to ensure that the scale build up does not block the working components. The safety surveillance systems are also quite complex, and are prone to failure due to the high heats sometimes experienced.
The other system presently used is a water spray that is directed into the circulating air/heat fan. The fan causes the water to break up into small particles and these are directed towards the heating elements or exchanger tubes. Because the flow of the air must pass by the elements or tubes, some of the water spray is lost, and has a non beneficial effect on the heating surfaces. The colder water may also run off the ovens hot surfaces, causing them to buckle and, or, cool. The end result can be an oven that has excess waste water coming from it and going to drain. In essence, the oven has a water cooling system instead of a steam generating system.
The heat inside the oven is circulated by one or more paddle type fans, and these can be multi-directional, so reversing their rotation during the bake may improve bake quality. Generally speaking however, the air is not well directed into specific areas of the oven, and is simply moved about as uniformly as possible.
When baking chickens, the fat and contents of baking is generally allowed to flow from the racks onto the floor of the oven. The oven floor is generally drained towards the middle and water and fat can discharge to waste. The ovens may have a self cleaning function, where in hot water sprays and chemicals and neutralizers are introduced at days end to clean the inner cell and components of fat build up etc. The oven floor is generally difficult to clean thoroughly because the fat drips constantly onto it, and then burns off, causing smoke and aroma contamination of the baked product.
It is an object of the invention to provide an oven design which overcomes one or more of the above problems.
Reference to any prior art in the specification is not, and should not be taken as, an acknowledgment or any form of suggestion that this prior art forms part of the common general knowledge in Australia or any other jurisdiction or that this prior art could reasonably be expected to be ascertained, understood and regarded as relevant by a person skilled in the art.